by Susan Page, USA TODAY

by Susan Page, USA TODAY

WASHINGTON â?? South Carolina Sen. Lindsey Graham said Thursday that former secretary of State Hillary Rodham Clinton should return to Capitol Hill -- under subpoena if necessary -- to answer new questions about the attacks on a U.S. consulate in Libya that left four Americans dead.

In an interview on Capital Download, USA TODAY's weekly video newsmaker series, Graham said the account of the Benghazi assaults last Sept. 11 offered by Clinton and other Obama administration officials had been undercut in congressional testimony Wednesday by three State Department officials, including Gregory Hicks, the No. 2 U.S. official in Libya at the time.

Hicks described a closer involvement by Clinton than previously known, including a phone call he received from her at 2 a.m. that deadly night. While the crisis unfolded, his pleas for a military response to the assaults were rejected. Afterward, he said he was castigated by Clinton's chief of staff, Cheryl Mills, for talking about the attack with a member of Congress who was visiting Libya.

Graham, a leading critic of the administration on Benghazi, said he had played a role in arranging Hicks' testimony.

"I got a call from a friend of his who said this Greg Hicks is really torn about what to do" about an official account of events he saw as inaccurate, Graham said. "So I got a phone number; I gave him a call. In March, we met here in the office. And I said, 'I don't know whether I can get the Senate to take this up, but the House is interested in finding out what happened in Benghazi.'"

He described Hicks as a reluctant witness. "He's probably the typical State Department person -- very diplomatic, very reserved -- but this was gnawing at him," Graham said. "It was really eating him up."

Hicks testified before the House Oversight and Government Reform Committee, chaired by Rep. Darrell Issa, R-Calif., a fierce Obama critic.

In January, before she left the administration, Clinton answered questions about Benghazi at a Senate Foreign Relations Committee hearing, angrily rebuffing suggestions that the administration had misled Americans about the attacks for political reasons, seven weeks before Election Day. At the time, United Nations Ambassador Susan Rice said in a string of Sunday morning TV appearances that the attacks might have been a spontaneous uprising sparked by an anti-Muslim video that had been posted on YouTube.

In fact, Hicks testified, he and other U.S. officials in Libya immediately realized it was a planned attack by terrorists.

Graham, interviewed in his Senate office, said Clinton should return to Congress to address the issues raised. Should she be subpoenaed?

"I hope she would come back without that, but yes," he replied. "I think she needs to come back and answer questions. Did she know that Cheryl Mills called the DCM (deputy chief of mission) to tell him, watch the member of Congress and don't talk to him? And there's now evidence that she was made aware of the security concerns and basically ignored security requests."

He said Mills and Gen. Martin Dempsey, the chairman of the Joint Chiefs of Staff, and others also should be called to testify about the attacks. Those killed included Christopher Stephens, the first U.S. ambassador to die in the line of duty in a generation.

Republicans began this week to more openly hold Clinton responsible both for inadequate security at the consulate before the attack and for misleading characterizations about it afterward. Graham denied the criticism was partisan or an effort to dent the reputation of the leading prospect for the Democratic presidential nomination in 2016.

He noted Democrats had praised him during the Bush administration when he faulted then-Defense secretary Donald Rumsfeld and then-vice president Dick Cheney on national security issues.

"When ... we were pushing back against Rumsfeld and Cheney about Iraq in the early years, as not going well -- it's not a few 'dead-enders' -- we were great patriots," he said. "When you question Secretary Clinton and President Obama, it's a little bit different from our Democratic friends."